engleski

Properties and Atomic Structure of Amorphous Early Transition Metals

Wide glass-forming ranges in TE-TL alloys (TE = Ti, Zr and Hf ; TL = Co, Ni and Cu) combined with often linear variation of their properties with composition makes it possible to predict the physical properties of the alloys which have not been prepared as yet (including pure amorphous TE). Recently, we explored this possibility for paramagnetic amorphous Zr-TL alloys in order to obtain parameters associated with the electronic structure and interatomic bonding of amorphous Zr. The comparison of these parameters with the results of the electronic structure calculations for different crystalline phases of Zr indicated an fcc-like local atomic structure for amorphous Zr. Here we provide new data for magnetic susceptibility () , superconducting transition temperature (Tc) and Young, s modulus (E) extending over a wide composition range of amorphous Hf-TL and Ti-TL alloys. We combine our results with published data in order to obtain a set of parameters appropriate to hypothetical amorphous Hf and Ti. As in the case of amorphous Zr these parameters are very different from those of stable crystalline phases (hcp) of Hf and Ti and indicate, as for Zr, an fcc-like short range order for amorphous Hf and Ti, too. This results in an enhanced electronic density of states at the Fermi level, N(EF) and thus in enhanced  and Tc, but in weakened interatomic bonding (low values of E and the Debye temperatures, D).

Metallic glasses; Superconductivity; Mechanical properties

nije evidentirano